import org.junit.jupiter.api.Test;

public class SingleInstance {
    //这里就先创建好了对象，调用SingleInstance中的instance就直接可以获取到一个单例对象
    public static SingleInstance instance= new SingleInstance();

    private SingleInstance(){

    }

    @Test
    public void test(){
        String  s1="s";
        String  s2="e";
        int a=1;
        System.out.println(a+s2);
    }
}




